In general, a small-sized camera module is mounted in mobile terminals such as smartphones. A lens driving device having an autofocus function of automatically performing focusing for capturing a subject (hereinafter referred to as “AF (Auto Focus) function”) is applied in such a camera module.
The auto-focusing lens driving device (hereinafter referred to as “AF lens driving device”) includes, for example, an auto-focusing coil part (hereinafter referred to as “AF coil part”) disposed at the periphery of a lens part, and an auto-focusing magnet part (hereinafter referred to as “AF magnet part”) disposed to be radially spaced apart from the AF coil part. An autofocus movable part (hereinafter referred to as “AF movable part”) including the lens part and the AF coil part is moved with respect to an autofocus fixing part (hereinafter referred to as “AF fixing part”) including the AF magnet part in the light axis direction by use of a driving force of a voice coil motor composed of the AF coil part and the AF magnet part, so that automatic focusing is performed (for example, Patent Literature (hereinafter, referred to as “PTL”) 1).
In a case where the AF movable part includes a lens holder configured to house the lens part and including the outer peripheral surface on which the AF coil part is disposed, the lens holder is provided with tying parts to which ends of the AF coil part are tied. These tying parts, when formed in such a manner as to protrude in the height direction (light axis direction) of the lens driving device, cause an increase in the overall height of the lens holder and thereby constitute a factor obstructing achievement of height reduction of the lens driving device. In addition, in a case where the AF fixing part includes a base member disposed to be spaced apart from the lens holder on the image formation side in the light axis direction, tying parts formed in such a manner as to protrude on the image formation side in the light axis direction also obstruct achievement of height reduction of the lens driving device since it is necessary to secure a suitable distance between the lens holder and the base member spaced apart from each other. Accordingly, the height reduction of the lens driving device has conventionally been achieved by forming the tying parts such that the tying parts radially outwardly protrude (for example, PTL 2).